1. Field of the Invention
This invention relates generally to lasing cavities, and more particularly to a system for dumping the resonant energy in such a cavity while other frequency modes are still resonating within that cavity.
2. Description of Prior Art
The use of both continuous and pulsed lasers are now well-known light generating devices. The main difference between continuous and pulsed lasers is the energy output for a given period of time. For pulsed lasers, which generally provide high energy output, an inherent limitation is the regeneration time of the laser while the resonating mode builds up between pulses. Previously, no lasers have been known which are capable of emitting a pulse of light while resonating in other modes.
Basic principles of mode selection in lasers can be found in the article "Mode Selection in Lasers" by P. W. Smith, Volume 60, Number 4, April 1972, pages 422-440 in Proceedings of the IEEE. The Smith article contains the description of the known reflection methods for oscillating light in a laser cavity and the respective emission spectrum that any given method of resonating provides. In particular, the Smith article discloses the emission characteristics when using either a Michelson or a Fox interferometer. As taught by Smith, the difference between these interferometers is the line width of the emitted light.
The use of a Michelson interferometer for controlling laser pulses in also well-known in the art as taught by U.S. Pat. No. 3,879,686 to Milam et al. The Milam et al. patent teaches using adjustments to the total path length difference between interferometer arms to control the laser pulse duration. U.S. Pat. No. 3,504,299 To A. G. Fox explains why a Fox interferometer has narrow bandwidth selection.